With the winding down of a year marking the 50th anniversary of the World’s Fair, Seattle and the Puget Sound region are trying very hard to make the next 50 years as successful.

The foundations are potent: Leading global clusters in aerospace, software and, increasingly, world health. Biotech and biomedical clusters are close behind. The region’s ports, on the Pacific Rim, are plugged in to the Asian Century.

This is a more diverse, prosperous and economically powerful place than the Seattle that boldly hosted the Century 21 Exposition half a century ago.

Still, predicting the future based on the present is risky. As it turned out, cities didn’t end up laced with monorails. Had you walked through the fair talking about software, most people might have thought you meant a garment for Elvis. Today startling numbers of Americans don’t believe in the fair’s organizing theme: Science.

Speculation must also account for surprises and game-changing events.

Will the Space Needle still be standing to mark its centennial? Over the next 50 years, a major earthquake could devastate Seattle. A Chinese-American war could get out of control, leading Beijing to use nuclear weapons against the nuclear-submarine base at Bangor.

Anxieties abounded in 1962. The Cuban missile crisis emerged as the World’s Fair was ending, perhaps the closest the world came to nuclear war. Yet that Armageddon never happened. The Soviet Union no longer exists.

With all these caveats, it is possible to look at some long-term trends and have a sense of the world in which Seattle will be competing.

Time is running out to prevent the worst consequences of climate change. Big oil and wishful thinking have won the day, and nothing will be done.

As a result, food supplies will be endangered and mass migrations will come out of future dust bowls and flood zones.

Tropical diseases will move north. Acidification will pose a major threat to sea life.

It will happen slowly, but it will happen, with horrific economic, environmental and social costs.

Americans still hold a childlike belief that technology can save us. Perhaps it will.

Science-fiction writer John Shirley has speculated about the emergence of “technocratic city-states,” whose elite residents are protected from the worst chaos and unrest. That could be Seattle in 2062.

If climate change is subtler, a defining event will come in 2030 if, as expected, China overtakes the United States as the world’s largest economy.

That doesn’t require us to be in absolute decline. We will be competing in a multipolar world with many large economies, including India and Brazil.

This could be a win-win world, especially for a state as trade-savvy as Washington.

For example, drought elsewhere might make our agricultural exports even more valuable.

But remember, a century ago very smart people believed that era’s globalization and interconnected trade had made war obsolete. Two years later, World War I commenced.

Since 1945, Pax Americana has avoided a conflict between major powers for the longest period in centuries. But dangers lie ahead.

Chief among them: The United Nations projects a world population of 9 billion by 2050. Many will be unemployed. A new generation of robots and automation could make jobs even more precious.

Also: competition among nations to secure limited supplies of energy and food; failed states and nuclear proliferation. Higher energy costs could undermine the 10,000-mile supply chain.

Inequality is at historic highs. We risk creating a permanent unemployable underclass. We risk being unable to govern ourselves.

One way or the other, this will be settled by 2062.

Whether Seattle is in what was once the United States of America is unclear. Regions might peacefully secede or the republic might become radically decentralized.

It is more comforting to look at our history, know we’ve gotten out of scrapes before, and imagine an even stronger America ahead. But it won’t just come from boilerplate or magical thinking.

In a future of megacities and mega-slums, Seattle will be competing against the so-called alpha cities, those that play the most important roles in the world economy.

While we won’t be the size of New York or Shanghai, such cities will be rivals to lure and retain talent and capital. And with that, create the technological revolutions to come.

The Swedish scholar Tomas Ries, writing for the U.S. National Intelligence Council as it prepares to release its closely watched Global Trends 2030 report next month, argues that alpha cities and mega-slums will disproportionately affect the world of the future.

“The alpha-city is emerging as a powerful stakeholder with vital global interests, including political and security. If the state can no longer ensure these interests, then the alpha-city will have no choice but do so on its own, or in consort with other alpha-cities. This rise of the alpha-city as a major global political actor is the first revolution.”

The second is the rise of mega-slums, seedbeds of unrest and terrorism.

This doesn’t mean the end of the nation-state.

However, Ries writes, “where the vitality and money goes, power tends to follow. And where the money is missing, and people mass, revolutions tend to explode.”

This is the world facing Seattle in 2062. The time to begin preparing for it was yesterday.